The University of California San Diego proposes to establish a Pediatric AIDS Clinical Treatment Group (ACTG). This Center will utilize the experience, expertise and core facilties already established for adults at the NIAID sponsored UCSD ACTG, and will include the additional investigators, facilities and laboratory capabilities necessary to perform pediatric studies. In cooperation with other Pediatric ACTGs and the NIH, the goal of this proposal is to establish a mechanism that ascertains that candidate drugs for the treatment of HIV-infected children are evaluated in safe, well-designed clinical trials as expeditiously as possible. There are no competing pediatric AIDS investigators in San Diego and Imperial counties (population greater than 2,000,000) and all other major providers of care for children in the counties have agreed to refer HIV-infected or at-risk children for evaluation and possible enrollment into chemotherapeutic trials,. Additionally, physicians at the two major pediatric centers in Orange County, University of California Irvine Medical Center and Children's Hospital of Orange County, have agreed to refer children to the UCSD Pediatric ACTG. Thus, virtually all children identified as HIV infected in San Diego and Imperial counties and most in Orange County will be available for treatment protocols resulting from this RFA. Currently, over 55 HIV-infected children receive care from members of the UCSD ACTG in San Diego, and over 20 infected children are receiving care from collaborating physicians in Orange County. Over the next five years, greater than 200 children can be predicted to be born HIV infected in San Diego County alone. The UCSD Pediatric ACTG has identified an outstanding group of investigators experienced with the pediatric and obstetrical issues relating to HIV infection. They have had extensive experience in the development, coordination and implementation of treatment protocols for patients infected with HIV. Additionally, the investigators have unique experience in developing analytical techniques with which to evaluate new drugs, perform pharmacologic studies, develop innovative diagnostic virology, and assess neuropsychologic development. This experience and commitment will ascertain that studies conducted by the USCD Pediatric ACTG will meet the highest standards of clinical research.